Emerging Applications of Bio-Inspired Algorithms in Image Segmentation

Image processing is one example of digital media. It consists of a set of operations to handle an image. Image segmentation is among its main important operations. It involves dividing the image into several parts or regions to extract vital information or identify relevant objects. Many techniques of artificial intelligence, including bio-inspired algorithms, have been used in this regard. This article collected the state-of-the-art studies presenting image-segmentation techniques combined with four bio-inspired algorithms including particle swarm optimization (PSO), genetic algorithms (GA), ant colony optimization (ACO), and artificial bee colonies (ABC). This research work aimed at showing the importance of image segmentation and its combination with these algorithms. This article provides insights on how these algorithms are adapted to image-segmentation combinatorial problems, which assist researchers to start the first hands-on application. It also discusses their setting parameters and the highly used algorithms such as PSO, GA, ACO, and ABC. The article presents new research directions in image segmentation based on bio-inspired algorithms.

Развитие технологии настройки акустических систем при ультразвуковом контроле сварных соединений

The urgent task is improvement of the accuracy of diagnosing the linear part of pipelines, structures and equipment of pumping and compressor stations, tank batteries, tank farm complexes. Therewith, it is required not only to identify a defect with a given probability, but also to ensure measurement of its shape and dimensions with accuracy to be sufficient to perform analysis of structures for strength and durability. The article deals with certain possibilities for increasing the detectability of volumetric defects, such as knots, through improvement of the methods for setting parameters of ultrasound pulse-echo testing. The results of research in the field of improvement of the technology for setting advanced ultrasonic systems using phased array antennas are presented. Cylinder-shaped drilled holes of different orientations have been reviewed as artificial defects for setting sensitivity and time base of the flaw-detecting instrument. Following on the earlier published works, the expediency of using vertical cylindrical drilling for setting the equipment is additionally justified: such target is the easiest to manufacture, its parameters are verified much easier than, for example, the parameters of flatbottomed holes. Examples are given of the practical use of drills of various orientations for adjusting sensitivity of monitoring and determination of the indication length of local bulk defects of the base metal and welds. Актуальной является задача повышения точности диагностирования линейной части трубопроводов, сооружений и оборудования перекачивающих и компрессорных станций, резервуарных парков, нефтебаз. При этом требуется не просто выявить дефект с заданной вероятностью, но и обеспечить измерение его формы и размеров с точностью, достаточной для выполнения расчетов конструкций на прочность и долговечность. В статье рассмотрены некоторые возможности повышения выявляемости объемных дефектов типа свищей за счет совершенствования способов настройки параметров ультразвукового контроля эхо-методом. Представлены результаты исследований в области совершенствования технологии настройки современных ультразвуковых систем, использующих фазированные антенные решетки. В качестве искусственных дефектов для настройки чувствительности и временной развертки дефектоскопа рассмотрены цилиндрические сверления разной ориентации. В развитие ранее опубликованных работ обоснована целесообразность применения для настройки оборудования вертикального цилиндрического сверления: такая мишень наиболее проста в изготовлении, ее параметры поверяются значительно проще, чем, например, параметры плоскодонных отверстий. Приведены примеры практического использования сверлений различной ориентации для настройки чувствительности контроля и определения условной протяженности локальных объемных дефектов основного металла и сварных швов.

The High-Reliability Optimization of Dead-Time Circuit for Push-Pull DC-DC Converter

Aiming at of the problem of common conduction state in push-pull DC-DC converter’s power transistor, an optimization solution by improving pulse width modulation(PWM) mode and reasonable setting parameters of the transformer and the inductance was proposed. The solution was analyzed in detail and test of the optimized circuit are carried out. The results show that the optimized circuit can effectively eliminate common conduction state, make the converter have a suitable dead-time and greatly improve the reliability of the converter.

Simulation model of PID for DC-DC converter by using MATLAB

The change in loads in most applications whose source of nutrition is a renewable energy system. Renewable energy systems can change according to climatic conditions. To control and control these changes, the use of conventional control systems such as PIDs. The PID is one of the most common and used conventional control systems that have been chosen to output the type of power electronic devise (DC-DC converter) in different working conditions. The current study aims to improve the system performance through simulation. Simulation results demonstrate the effectiveness of the system with the controller based on setting parameters such as recording system states, embedded elevation time and transient response.

Vertical Graphene Growth on AlCu4Mg Alloy by PECVD Technique

Vertical graphene, which belongs to nanomaterials, is a very promising tool for improving the useful properties of long-used and proven materials. Since the growth of vertical graphene is different on each base material and has specific deposition setting parameters, it is necessary to examine each base material separately. For this reason, a full factor design of experiment was performed with 26 = 64 rounds, which contained additional 5 central points, i.e., a total of 69 rounds of individual experiments, which was to examine the effect of input factors Temperature, Pressure, Flow, CH4, Plasma Power, and Annealing in H2 on the growth of vertical graphene on aluminum alloy AlCu4Mg. The deposition was performed using plasma-enhanced chemical vapor deposition (PECVD) technology. Mainly, the occurrence of graphene was analyzed, which was confirmed by Raman spectroscopy, as well as its thickness. The characterization was performed using electron and transmission microscopy, including an atomic force microscope. It was found that the growth of graphene occurred in 7 cases and its thickness is affected only by the interaction flow (sccm) × pretreatment H2 (sccm).

Method of Predicting the Crimp of Jacquard-Woven Fabrics

The aim of this study was to investigate the distribution of crimp in new jacquard fabric structures (in which one-layer and two-layer weaves are combined) in the fabric width and to create a method of crimp prediction. It was established that crimp was around 18.80% and changed within the limits of errors, i.e., a range of only ~4%, in the fabric width. It can therefore be said that the warp crimp was constant in the fabric width. Because the warp crimp of jacquard fabric changed insignificantly (within the limits of errors), it can be stated that the fabric-setting parameters and structural solutions were chosen and matched correctly, and such fabric can be woven on any jacquard weaving loom.

Demand Driven Material Requirements Planning (DDMRP): A systematic review and classification

Purpose: Demand Driven Material Requirements Planning (DDMRP) aims to deal with variability by adjusting inventory levels while maintaining, or even increasing, customer service levels. This approach bridges the push and pull approaches. Even though it first made its appearance in 2011, research in this field remains relatively limited. This paper aims to measure the spatiotemporal evolution of the DDMRP, its scope and context of implementation, and the research lines studied in that field in order to identify areas that still need to be addressed by future researchers.Design/methodology/approach: The systematic literature review approach adopted in this paper examines research dealing with the DDMRP approach published in different languages between 2009 and 2020. To-date papers focused on the performance analysis and comparison, what differentiates this study is the focus on the scientific evolution level of DDMRP, the parameters, and contexts that should be more studied.Findings: The results show that DDMRP is not yet a mature method and that the robustness of the approach still needs to be tested. More research is also required to determine scientifically some setting parameters, how the proposed DDMRP could be implemented in different industrial contexts with existing information systems.Originality/value: Based on the evolution analysis of DDMRP, this study outlines its current state of maturity and its different shortcomings under a broader vision to make this method more complete on the scientific and industrial level.

Object Pose Estimation for Robot Loading in Accommodation Space Using Alpha-Shape Algorithm

Robots with visual sensors have been used in various goods logistics, such as bin picking or uploading. However, there are more and more demands for the automatic blanking and loading, it is necessary to solve the problem of object pose estimation in changing accommodation space. This paper proposes a method for pose estimation in the accommodation space using alpha-shape algorithm and improved Fruit fly Optimization Algorithm (FOA). The alpha-shape volume variety of object and measured space is set to the objective function and the pose variety of object is set to six variables of improved FOA. The experiments were performed by setting parameters of improved FOA and considering the four space types represented the common accommodation shapes. Compared with previous work using convex hull, the new study using alpha-shape algorithm not only keeps the object in the accommodation space, but also maintains the object pose is at the bottom of the space and can meet the practical requirement of object placement by robot arms.

Joint impacts of relaying scheme and wireless power transfer in multiple access of cellular networks

This paper considers ergodic capacity of energy harvesting (EH) based cellular networks. Such a network employs non-orthogonal multiple access (NOMA) together with relaying scheme to serve two far users. In this system model, relay is facilitated power splitting (PS) protocol to implement energy harvesting (EH). To examine capacity, expressions of signal to noise ratio (SNR) need be computed to achieve capacity. Power allocation factors are different for two users in such system and hence performance gap happens to distinguish requirements for separated users. It can be confirmed that the proposed paradigm exhibits maximal achievable capacity in some scenarios of setting parameters. To confirm exactness of the analytical expressions and show advantages of the proposed EH-NOMA, simulation results are performed in terms of ergodic capacity.

Unknown Parameter Excitation and Estimation for Complex Systems With Dynamic Performances

Simulation models play crucial roles in efficient product development cycles, therefore many studies aim to improve the confidence of a model during the validation stage. In this research, we proposed a dynamic model validation to provide accurate parameter settings for minimal output errors between simulation models and real model experiments. The optimal operations for setting parameters are developed to maximize the effects by specific model parameters while minimizing interactions. To manage the excessive costs associated with simulations of complex systems, we propose a procedure with three main features: the optimal excitation based on global sensitivity analysis (GSA) is done via metamodel techniques, for estimating parameters with the polynomial chaos-based Kalman filter, and validating the updated model based on hypothesis testing. An illustrative mathematical model was used to demonstrate the detail processes in our proposed method. We also apply our method on a vehicle dynamic case with a composite maneuver for exciting unknown model parameters such as inertial and coefficients of the tire model; the unknown model parameters were successfully estimated within a 95% credible interval. The contributions of this research are also underscored through multiple cases.